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Making sure the lights don’t go out

Based on the state of our current power grid system, load shedding has become a necessary evil as it reduces the risk of a national blackout that could take the country a week to recover from. But that doesn’t reduce the business impact or lessen the blow, therefore it is critical for businesses to make alternative power arrangements.

Running a generator is still the costliest power source in the long run and putting all of your devices onto an alternative power system isn’t financially viable or practical. Instead, what businesses should be doing is deciding what their core energy requirements are and then building a solution to fit these requirements. If you need to power your computers, lights, boardroom, access control system, security system and possibly some additional plugs, the system you require is going to cost a lot less than one that needs to power your entire powered environment, including air conditioners, kettles, geysers etc.

According to Inus Dreckmeyr, CEO at Netshield South Africa, the best alternative is building a power solution that supports a well thought-out and calculated power requirement for your exact use case. It is with this that the Netshield inverter/charger range, a true sine wave inverter and high-power battery combination solution, can be used in three use cases, namely: high-power deep cycle line interactive UPS mode, as a grid assisted or as a generator and grid assisted energy source.

“Quintessentially, you want the most cost-effective and efficient solution you need to minimise the load you want to run on the unit, and combine it with renewable energy sources you can partially feed from. In this case you can then create an environment where you always use renewable first, revert to the grid to top up/charge your environment if needed or failover to generators if Eskom just isn’t available – there will be a future return on investment for reducing your reliance on the grid with this use case.”

As the units can source power from either the power utility feed, a backup diesel generator or solar arrays, their optimal deployment can only be achieved if you have accurately calculated the size of your critical load and the required backup time frame. However, as it is often difficult to determine the amount of time that the power is down, in the case of load shedding we know it could be up to 4,5 hours, so you can add additional batteries to its scalable battery bank that will then serve as the primary power source if there is no power being received from any other power sources.

The size and costs of the Netshield units are entirely dependent on the desired application, the size of the installation and the existing infrastructure you would like it to connect to. Ensuring that your power consumption is optimised not only reduces the cost of a smart power backup system, but also reduces the day-to-day cost of running a business. According to Dreckmeyr, the units can be naturally expanded with the addition of photovoltaic panel arrays (solar panels). An intelligent gateway can also be added if visibility is required into managing differing power sources.

Use case for the Netshield inverters

High-power, deep cycle line interactive UPS mode: In the event of load shedding or an unstable grid connection, the unit will kick into the high-power deep cycle line interactive UPS mode and will switch over into online mode within 12 milliseconds. This mode relies on the battery charge being maintained by the grid power when it is available.

Grid assisted mode: The grid assisted inverter mode is a hybrid mode, where you can run a grid connection in conjunction with additional renewable energy resources, like solar panels. In this instance, the inverter and renewable energy source will be the primary energy feed and will only switch over to the grid supply in the event that this supply has run out and the batteries need to be recharged. Once recharged it will automatically switch back to the inverter.

Generator-assisted mode: If you are ‘off the grid’ this is where the generator-assisted mode will be the most suitable. Batteries are charged by photovoltaic solar panels and/or wind generators, however if the renewable resource or utility power and/or the battery sourced power doesn’t service the actual required load, the inverter will switch over to an installed generator. While the generator is running it will concurrently charge the unit’s batteries and once the charge has been met, it will automatically switch back to the inverter, optimising the required run time of the generator as it is switched off once the batteries have recharged.

The Netshield units are designed to act as the core of a reliable power feed and supply from 1 kVA to 12 kVA continuously, with a battery charging capability of up to 10 to 120 A depending on optimisation product selection.

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